birrell



Patented lune 20, [899.

a. BIRRELL. POWER TRANSMITTER.

(Application led May 1.5, 1897. Renewed Nov. 25, 1898.)

2 Sheets-Sheet 2.

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Nrrnn *rares GEORGE B. BIRRELL, OF NEW YORK, N. Y., ASSIGNOR TO TIIEBIRRELI. UNIVERSAL TRANSMITTER COMPANY, OF SAME PLACE.

POWER-TRANSMITTER.

SPECIFICATION forming part f Letters ient NO. 627,383, dated J une 20,1899. Application filed May 15, 1897. Renewed Novem-'ber 25,1898. SerialNo. 697,468. (No model.)

To all who-m t may concern.-

Be it known that I, GEORGE B. BiRRnLL, a

' citizen of the United States, and a resident of New York city, in thecounty of NewYork and State of New York, haveinvented a new and usefulImprovement in Power-Transmitters, of which the following is aspecification.

My invent-ion relates to that class of powertransmitters for impartingmotion, and thereby transmitting power, but at a different rotary speed,from a shaft or prime mover to another shaft or final mover in line.with or concentric to the prime mover, said transmission of motion andpower being accomplished without the use of a counter or jack shaft, butby means of certain combinations of gears, as will be hereinafterexplained.

The object of my invention 4is to endow the class of power-transmittersreferred to above with a functional feature which they have notheretofore possessed-viz. the possibility while the prime mover ismoving steadily and lcontinuously at a given speed of varying at willthe speed of the final mover in the same direction as the prime mover orin the opposite direction.

y My invention consists in constructing a power-transmitter of the classnamed with several sets or trains of gears having different ratios ofdifferentiationl and in mechanically so arranging such trains of gearsthat while all of them are at all times in coaction they run idle untilsuch time as a fulcrum is provided` without stopping or reversing theprime mover and to the extent also that all the gears may be thrown outof action land run' idle, so that the iinal mover will stop with theprime mover still going at full speed.

In the drawings, Figure l is a vertical longitudinal section through thecenter of the prime movers of one of the simplest forms of mytransmitters, wherein motion and power are transmitted from one to theother of two shafts in line with each other. Fig. 2 is a verticalcross-section through line :r y, looking to the right. Fig. 3 is ahorizontal crosssection through the axis of the shafts, which are shownconcentric with each other, the particular form of my inventionillustrated being one of those which I will use for a trolley orelectrically-propelled car. In this case the prime mover or motor-shaftis in the form of a sleeve concentric with the final mover or car-axle.In this figure for the sake of making the drawing clearer the'transmitters are drawn to a scale larger than that of the axle andcar-wheels.

In Figs. 1 and 2, A is the driving-shaft or prime mover in line with andconcentric to the secondary or final mover or driven shaft B. O is acasing having a base D and a lid or cover E, by means of which thecasing may be made both dust-proof and oil-tight. The shaft A carries aneccentric F, on which fits loosely (without being keyed thereon) a wheelG. This wheel carries on one side an external gear H and on the otherside three gears-two internal, I and J, and one external, K. The fourgears on the wheel G are concentric with each other and with theeccentric F.

They are therefore eccentric to the center of t-he shafts to the extentof the throw of eccentric F. Ooncentric with the shaft B and securelykeyed or fastened thereon is a bushing or sleeve L, carrying aninternal-gear wheel M, the pitch diameter of which exceeds the pitchdiameter of gear H bytwice the eccentricity of the eccentric F. Itfollows that the gear M engages deepest with the gear H on the linerunning through the center of the shafts and the center of the eccentricF and at the end of that line nearest the eccentric, while at the otherend of the line the two gears are withdrawn from each other to themaximum extent. It follows also from lthe relative dimensions ofthegears II and Mthat as the prime mover A and the eccentric F are revolvedthe gear II will revolve tooth for tooth inside the gear M, and as thepoint of contact rotates with the eccentric and as the numbers of teethon the two gears are different, owing to the difference in thediameters, the angular velocity must be different. This IOO relation ofsizes between gea-rs G and M applies to all the pairs of gears, oneeccentric to and the other concentric to the axis of shafts, which I usein mesh with each other in my transmitter. I mean to say that in eachand every such pair or train of gears, regardless of the size of thegears, the pitch diameter ofthe external gear exceeds that of theinternal gear by twice the eccentricity of theeccentric.Meshing,respectively,with the two internal gears I and J and with theexternal gear K on the wheel G are two external gears N and O and aninternal gear I. These gears are all three concentric to the shafts andare mounted, respectively, on three ttings Q R S, which fittingsterminate to the left in sleeves fitting over one another, the innerone, S, fitting over the prime mover, butnotinanywaysecuredthereto. Theouter fitting or sleeve Q revolves in a journal U, formed on or securedto the casing C, and in the lid E there is another journal V in linewith U, in which revolves the sleeve L of the gear M, which, as statedbefore, is secured to the final mover B. The sleeve ends of the fittingsQ R S project beyond the box or joui'- nal U and in steps, as seen atFig. l, so as to admit of each one having securely fastened to it a bandor brake wheel W IV XW. It should be carefully noted that each of thewheels or gears O P N forms with its corresponding sleeve andbrake-wheel one solidlyconnected body, each of these bodies beingperfectly independent of each other or of the motions of each otherrelatively to itself and independent also of the shafts. By clamping anyone of the brake-wheels \V lV XV2 it is evident that the fitting andgear-wheel to which it is attached will be prevented from revolving andremain stationary independently of the other gears. X is acounterbalance -weight permanently fastened on, the shaft A and intendedto counterbalance the eccentric F and wheel G. The right-hand end ofshaft A is shown stepped or journaled into shaft B tosecure rigidity.

In Fig. 3 I employ a system of referenceletters independently of Figs. land 2 for the purpose of avoiding any confusion. A represents thecar-axle, carrying the wheels B B and trunnions C C. D' is the armatureof the motor, permanently fastened on the hollow shaft or sleeve S,which is suitably journaled on the car-axle A. E and E are two casingsset in line with each other and se cured by the horizontal sidetraverses F F, which latter also carry the field-pieces G G of themotor. The casings E and E carry journals H and Il', bored in line witheach other, and also covers I and I to make the casings both oil-tightand dust-proof. Ateither end of the hollow motor-shaft S is securelyfastened an eccentric K and K2. These eccentrics are of the same throw,the same diameter, and the same face and are set diametrically oppositeto each other. The eccentric K carries a loose wheel L, on which ismounted on one side a gear M, meshing with a gear O, thesupporting-wheel or fitting of which is permanently fastened to thecai'- axle. rPhe eccentric K2 carries a loose wheel P, on which ismounted on one side a gear Q', meshing with a gear R', thesupporting-wheel or fitting of which is permanently secured to thecaraxle A. Both the secondary gearwheels O and R are concentric to theshafts. The wheel L carries on the side opposite gear M three gears (inthis case two internal and one external) meshing, respectively, withthree corresponding gears (two external and one intern al) concentricwith the shafts. The supporting-wheels or fittings S' T U of theselatter gears correspond with those shown in Fig. l at Q R S, and theyare likewise entirely independent of the driving-shaft and of cach otherand are each provided with a rigidlyfastened brake-wheel V' V2 V3,having shoes X X2 X3. The wheel I)l carries on the side opposite gear Rthree gears (in this case one external and two internal) meshing,respectively, with three corresponding gears concentric with the shaftand mounted on fittings a, ZJ c, having solidly-fastened brakewheels dcf, with brake-shoes g h i. There are also two brake-wheelsj and j, withshoes 7a and k fastened rigidly on the car-axle. Z represents a rheostatdivided into seven sections, six of which correspond, respectively,

with the brake-wheels V' V2 Vsfc d, so that the placing of the handle ofthe rheostat in any one division will electrically tighten theshoe-brakes of the corresponding wheel and thereby lock thecorresponding gear. The seventh division, which is not lettered,corresponds with the two brake-wheels j and j on the axle, and theplacing of the handle on the said division will apply the brakes directon the axle, which, none of the gears being locked, will receive noimpulse from the mo tor-shaft, although the latter will still be runningat its full speed. in this construction no counterbalance is shown forthe reason that none is needed. The eccentrics from their location andconstruction described above balance each other, so that by making thewheels L' and Pwith the gears thereon (whatever be their size ordiameter) of equal weight, these Wheels being of symmetrical figure andtherefore their center of gravity at the center of their respectiveeccentrics, a perfect equipoise is provided for under all speeds andconditions. It should also be noted that the construction shown isentirely supported by the car-axle and can therefore be made entirelyindependent of the car-body except to the extent that a pin orprojection from the motor should encounter a corresponding projection onthe car-body to prevent the structure from revolving.Otherwiseandforallpurposesmytransmitting mechanism is entirelyindependent of the car-body, thus permitting it to be readily removedfor repairs, thc.

I do not wish to limit myself to the partic- It will be noticed that XOOIIO

nlar selection or combinations of gears shown in the drawings, as theysimply serve to illustrate the scope of my invention, which is broadenough to comprehend any desired combinations of gears to produce anyrequired series of speed differentiations either in the direction of theprime mover or the opposite one.

I will now explain the practical working of my invention.

Referring to Fig. 2, consider the gear I fastened to the wheel Gand thegearN concentric to the shaft A and imagine that the gear N is heldstationary. Then suppose that the gear I has two hundred and thirty-sixteeth and the gear N has two hundred and twentyeight. If now the shaft Aand eccentric F are revolved one full turn in the direction of thearrow, the point of contact will revolve a full turn around and theenveloping gear I will roll tooth for tooth on the inner one, N, withthe result that when the full turn is completed the tooth on the gear Iwhich originally stood at the point of deepest contact- 11. e., on theVertical line through centers of shaft and eccentric-will have passedthatline to the left-that is, in the direction of the circular arrowbyeight teeth, the rolling contact with thetwo-hundred-and-twenty-eighttoothed gear N having only called for twohundred and twenty-eight of the two hundred and thirty-six teeth on gearI. Therefore it is evident that while the shaft A made a fulllrevolution the wheel G only made eight twohundred-and-thirty-sixths orabout two fiftyninths of a revolution in the same direction. Nowconsider the external gear K on the wheel G and the internal gear Pconcentric with the shafts and let us suppose that while the latter gearP is held stationary the shaft A and eccentric F are revolved one turnin the direction of the arrow. Let us also suppose that K andP haverespectively one hundred and fifty-four and one hundred and sixty-twoteeth. As the rolling contact takes place tooth by tooth, before theeccentric can come back to its original position the one hundred andsixty-two teeth of the stationary gear K called forone hundred andsixty-two toothcontacts with gear P, and as the latter has only onehundred and fifty-four teeth it follows that the original deepestcontact-tooth on gear P has failed to return to its original position byeight teeth. In other words, theV gear P has swung an arc of eight teethin the direction opposite to that of the prime mover, so that when theshaft A turned one revolution the gear P moved eightone-hundred-andfifty-fourths or four seventy-firsts of a turn in theopposite direction. The above two examples thus show that when the primemover and eccentric are revolved in a given direction an internal gearon the wheel has an angular motion relatively to the external gearconcentric to the shaft with which it meshes in the direction oftheshaft, while an external gear on the Wheel has an angular motion in theopposite direction to that of the shaft relatively to the internal gearconcentric with the shaft with which it meshes.

Now let us consider, Fig. 1, the gear N, having two hundred andtwenty-eight teeth, supposed for the time being to be held stationary,gear I on wheel G with two hundred and thirty-six teeth, gear H on wheelG with two hundred and twenty-eight teeth, and internal gear M twohundred and thirty-six teeth integral with the final mover. Onerevolution of the wheel G would leave the tooth on gear M originally atdeepest contact eight .teeth behind the tooth on gear M with which itmeshed before the turn was' given, or, inversely, we may say that foreach revolution of the shaft A and eccentric F the gear M will havereceived an angular advance of eight teeth relatively to H and in thedirection of the rotation of the shaft. Now N, being stationary, oneturn of the shaft A causes the gear N to gain an advance of eight teeth,an angular advance of eight tWo-hnndred-andthirty-sixths of a turn inthe direction of rotation of the shaft. vThis angular advance of eighttwo-hundred-and-thirty-sixths of aturn corresponds to one of eighttwo-hundred-andthirty-sixths by two hundred and twentyeight, or 7.728teeth on gear I-I. AsH meshes tooth for tooth with M, it follows thatthe rotation of I on N-has forced M ahead 7.228

teeth. On the other hand, as explained before, the rotation of H in Mforced the latter eight teeth ahead. The total advance of M is then7.728 plus eight teeth, an angular ad- 236 In other words, for each fullturn of the prime mover A the final mover B, attached to the gear M,makes one-fifteenth of a turn, or, in other Words again, the relativespeeds of the two shafts are fifteen and one.

The combination' above described of one stationary gear concentric withthe shafts and a gear concentric and secured to the final mover, thesegearsmeshing, respectively,with two gears on a Wheel revolving looselyon an eccentric on the prime mover, is not a new one and has foundnumerous practical applications in various forms. Its usefulness,however, is limited by the fact that one gear-the fulcrum-gear, if I mayso term it-has to be stationary, and therefore only one fixeddifferentiation of speed is possible between the final and the primemovers.-

There are innumerable instances in the transmission of power, especiallyso when the prime mover has a high rotative speed, where it would be ofthe highest practical advantage to be able to vary at will the speed ofthe final mover and even reverse said final mover without stoppingor inany way altering the speed of the prime mover, and it is Vance of orone-fifteenth of a turn.

for the special object of meeting the requirements of such cases that Ihave evolved the IOO IIS

present invention, producing by means of it tainable.

In Fig. 1 the three gears O P N, concentric with the shafts, theirsupporting sleeves or ttings Q R S, and the brake-wheels YV IV )V2 areshown and described as being perfectly loose and independent of eachother, although, of course, each gear is rigidly connected with itscorresponding brake-wheel. I will explain what takes place when theprime mover A is revolved. The resistance of the nal mover will hold thegear M stationary. The gear H will roll on M, andk on the principleexplained before for each revolution of the prime mover and eccentricthe gear H will swing eight teeth in the direction oppo; site to that ofthe shaft an angular movement of eight two-hundred-andtwentyeighths of aturn, which angular movement amounts to eighttwo-hundredandtwenty-eighths multiplied by two hundred and thirty-six,or 8.28 teeth, on the gear I. Again, the revolution of the eccentriccauses the gear N byits rolling action inside of gear I to move eightteeth, in the direction opposite to that of the shaft, so that the totaleffect on gear N of one full revolution of the prime mover is to swingthis gear N 8.28 plus eight, or 16.28`

teeth in the direction opposite to that of the prime mover. Thisrepresents an angulai- 228 Hence for every turn of the prime mover thegear N and its brake-wheel W revolve onefourteenth of a turn in theopposite direction. In a like manner the gear O (O having one hundredteeth and .I one hundred and eight) and its brake-wheel W2 will move forevery turn of the motor and in the opposite direction eighttwo-hundred-and-twenty-eighths multiplied by one hundred and eight pluseight,

11.784 or l 100 8.49 of a turn. On the other hand, the gear P (P havingone hundred and sixty-two and K one hundred and fifty-,four teeth) andits brake- Wheel NV will move for every turn of the prime mover eighttwo-hundred-and-twentyeighths multiplied by one hundred andiftyfour-Viz., 5.4 teeth in the opposite and eight teeth in the samedirection, or eight less 5.4 equals 2.6 teeth in the same direction asthe shaft. This corresponds with an angular motion of or Thus with themechanism shown in Fig. I when the prime mover is running and thebrake-wheels free we will have the final mover at rest, the brakewheelsW and W2 revolving at reduced speed in the direction opposite to that ofthe motor and the brake-wheel Wl moving ata reduced speed in the samedirection.

Now supposing it be desired to start the final mover then clamp thebrake-wheel lV, thereby rigidly locking the gear N. At each movement of,or one-fourteen th of a turn.

or 11.784 teeth; in other words,

of a turn.

revolution of the eccentric the wheel G revolves eighttwo-hundred-and-thirty-sixths of a turn ahead, or eighttwo-hundred-andthirty-sixths multiplied by two hundred and twenty-eightequals 7.728 teeth on gear H, which latter gear forces gear M ahead thatsame amount of teeth plus eight, dueto its own intrinsic action on M.The latter receives, therefore, a total angular advance of LQ'Sl-, orone-fifteenth of a turn, in the direction of the prime mover. The onlyrequisite is that the grip of the shoes on the brake should besufficient to hold the brake-wheel rigid and stationary against theresistance of the final mover, said grip on the brake providing thefulcrum through which to exert the power. In the same manner thetighten= ing of the brake VV2 will cause the final mover A Q 24.88 lplus mgm, 01. 24.83, 01-

equals m 0f a turn in the direction of the prime mover. The tighteningof brake-wheel W will cause the final mover to revolve eight teeth iuthe direction of the prime mover and eight onehundred-and-fifty-fourthsmultiplied by two hundred and twentyeight, or 11.84 teeth, in theopposite direction, the result being that the final mover will be drivenat a rate of 3.84 or 1 236 9.48 prime mover.

It will be readily understood that great advantages ensue from myinvention in the ability t0 thus vary the speed and direction of thefinal mover with the first mover going steadily at a continuous speed.These advantages are further illustrated in the ar rangement of myinvention shown in Fig. 3.

Without repeating the calculations again I will say that the proportionsof gears shown give the following speeds: With brake V2 clamped axlebacks at aspeed of one to 8.92. W'ith brake f clamped axles back at aspeed of one to 56.58. With brake 7c 7c axle stops and is braked. Withbrake c axle goes ahead at a speed of one to 57.65. )Vith brake d axlegoes ahead at a speed of one to twenty-six. With brake V axle goes aheadat a speed of one to 9.95, and with brake V3 axle goes ahead at a speedof one to 6.65.

The brakes I propose to use in connection with all transmitters of whichthe prime mover is electrically operated are electricallyoperatedbrakes. They will be controlled by a rheostat having its segmentsconnected with the several brake-shoes in such a manner that no twobrakes (except the two on the axle) can be locked at the one time.Furthermore, I arrange the connections to the several brakes in such anorder on the dial of the rheostat that. it is not possible for theoperator to shift directly from a very high to a very low train ofgearing, or vice versa, without in so doing in the oppostedirection tothe IOO IIO

throwing into action intermediate trains of gearing for a period of timewhich, however small, will be sufficient to prevent any jerky action ofthe mechanism. Likewise the final mover or axle cannot be reversedwithout the brakes having been applied thereto. I do this by connectingthe wires between brakes and rheostat in such a manner that all thewires to the backing-brakes are on one side and all the wires to thego-ahead brakes are on the other side of that section of the rheostatwhich actuates the direct axle-brakes 7e 7o. Furthermore, the succeedingsections of the rheostat, both on the go-ahead and on the backing side,are in the order of the amount of differentiality of the particulartrains of gears to which each section corresponds, the section either togo ahead or back which corresponds with the train of minimumdifferentiality-that is, the one which propels the axle at the maximumspeedbeing the one farthest away from the full-stop action. This isclearly illustrated in Fig. 3, where section 5 corresponds with ahead atone to 57.65. Section 6 corresponds with ahead at one to twenty-six.Section l corresponds with ahead at one to 9.95. Section 3 correspondswith ahead at one. to 6.65. Section t corresponds with back at one to56.58, and section 2 corresponds with back at one to 8.92.

Suppose a car is being driven at full speed, the handle of the rheostatbeing in section 3, and it is required to stop it. The operating-gearinggives a rate of speed between movers of one to 6.65; but before theoperator can bring the handle to the f ull-stop section and thereby putthe brakes on the axle, he has necessarily during this movement of thehandle (no matter how quickly performed) actually gone through thefollowing operations: first, he freed the 6.65 to one train of gears,No. 3; then threw into action the 9.95 to train No. l; next freed No. land threw into action the twenty-six to one train No. 6, freed thelatter and threw into action the 57.65 to one train No. 5, and finallyfreed the latter to put the brakes on the axle. These successive changesin the rate of differentiality of the successive trains of gearingbrought into action in the act of stopping will have the result ofproducing a cushioning effect and of avoiding jars and jerks. As Istated above, the particular combination of trains of gears shown wasselected to illustrate the invention and its possibilities. I do notlimit myself to it, and in factI should in practice seek to make therate of variation of dierentiality in the successive trains more uniformthan mentioned here.

To still further enhance the cushioning effect, I propose to divide thesections of the rheostat into subsections so arranged electrically thatthe brin ging of the handle ofthe rheostat into these subsections shouldcause varying amounts of pressure to be exerted on the one brakecorresponding with the section of which these subsections are part. In

any one section the subsection corresponding with the greatest amount ofpressure exerted on the brake will always be on that side of the sectionfarthest removed from the fullstop section. The handle being in thisfull subsection,the brake willbe absolutely locked and the full speedcorresponding to the particular train of gears in action will berealized on the axle. As the handle is shifted to the next subsectionless power will be exerted on the brake, which will be allowed to slipto a'certain extent, the axle therefore revolving at a speed slower thanthat due to the train of gears in action if its brake were rigidlylocked, but a speed still in excess of that due to the next slowesttrain of gears.

It is evident that the cushioning effect will exist at starting as wellas at stopping, whether going ahead or backing.

Another very important practical feature of my invention lies in thesaving which it will effect in the cost of motors.

In present trolley-car practice, the motor being geared permanently tothe final moverin other words, the leverage being constant through whichto apply the power to the axleit follows that if a certain size of motoris sufflcient to keep a car running when once it is at speed this samemotor is entirely inadequate to the task of starting the car from astandstill. Hence the present necessity for carrying motors out of allproportion to the work to be done when the car is once under way and yetbarely sufficient to produce the starting effect. The use of thesemotors and the conditions under which they work requires that they shallbe series-wound and also involves the carrying of resistance-coils.

IOS

As the result of my invention, wherein the leverage is, if I may so termit, adjustable, it will readily be perceived that a motor sufficientlylarge to run the car at full speed is also sufficient to start it bysimply bringing into action a train of gears of sufficiently greatdifferentiality and as the car acquires IIO momentum successivelythrowing into action successive trains of diminishing differentialityuntil full speed is reached. Resistancecoils can be dispensed with andshunt-Wound motors used, and even storage batteries will becomepracticable, as they will be relieved of the heavy drain at startingattending present permanent gearing.

Owing to the practically frictionless operation of the gears I use, highrates of differentiation of speed between prime and final movers becomepermissible, which losses by friction entirely preclude in ordinary spuror worin gearing, and therefore very high speed, and consequently cheap,light, and economical motors, may be used with all attending advantages.

I wish it distinctly understood that I do not limit my claims to theforms of my invention shown and described; neither do Iwish to confinemyself to the use of electricallycontrolled brakes described. I reservethe right to use any kind of mechanically-operated brakes, but ofwhatever kind I prefer to operate them in such a manner relatively toeach other as to produce the cushioning effect described.

In lieu of the friction-brakes illustrated it will be understood that Imay employ any suitable equivalent means for checking, stopping, orcontrolling the rotation of the fulcrunl-gear wheels at will, and itwill also be understood that I do not wish to be limited tothe toothedform of gears shown, as any other suitable kind of gear-wheels may beemployed which are capable of producing the described action.

In Figs. l and 2, it will be seen, I have shown the several rolling-gearwheels in the form of a single eccentrically mounted and driven wheelhaving the different gears formed thereon and engaging severalsuperposed fulcrum-gear wheels. In Fig. 3 I have shown not only suchplurality of rolling gears on a single eccentric for varying the ratioas well as the direction of motion, but I have also shown such variationboth of ratio and direction of motion produced by a plurality of rollinggears on separate eccentrics engaging separate fulcrum-gear wheels andseparate secondary-gear wheels. My present in vention therefore covers,broadly, the plurality of rolling and fulcrum gear wheels for producingsuch variation of ratio of motion of the secondary-gear wheel eitherforward or backward with respect to the primary shaft, whether theseveral rolling-gear wheels are on the same or on separate eccentricsand whether the fulcrum-gear wheels are superposed or separate. Themotion imparted to what I term the secondary-gear wheels M in Figs. land 2 and O'R in Fig. 3 may, it is evident, be communicated to othermechanism either through their shafts, as shown, or in any othersuitable manner.

IVhat I claim as my invention, and desire to secure by Letters Patent,is-

l. In a power-transmitter, the combination of instrumentalities hereindescribed asa revoluble primary shaft, an eccentric fixed thereon, aplurality of fulcrum-gear wheels concentric with said shaft andrevoluble independently thereof and of each other, means for controllingthe rotation of the fulcrumgear wheels independently of each other, asecondary-gear wheel concentric with the primary shaft and revolubleindependently thereof,and a plurality of eccentrically mounted anddriven gear-wheels rolling on the respective fulcrum-gear wheels andhaving a gear rolling on the secondary-gear Wheel, said plural rollinggears and hence the secondary gear rotating in the same direction, butat different rates,whentheir respective fulcrumgear wheels are held.

2. In a power-transmitter, the combination of instrnmentalities hereindescribed as a revoluble primary shaft, an eccentric fixed thereon, aplurality of fulcrum-gear wheels concentric with said shaft andrevoluble independently thereof and of each other, means for controllingthe rotation of the fulcrumgear wheels independently of each other, asecondary-gear wheel concentric with the primary shaft and revolubleindependently thereof, and a wheel mounted loosely on the eccentrichaving a plurality of gears rolling on the respective fnlcrum-gearwheels, and having also a gear rolling on the secondarygear wheel, saidplural rolling gears and hence the secondary gear rotating in the samedirection, but at different rates, when their respective fulcrum-gearwheels are held.

3. In a power-transmitter, the combination of instrumentalities hereindescribed as a revoluble shaft, an eccentric fixed thereon, asecondary-gear Wheel concentric with the primary shaft and revolubleindependently thereof, a plurality of fulcrum-gear wheels concentricwith said shaft and revoluble independently thereof and of each other,means for controlling the rotation of the fulcrumgear wheelsindependently of each other, and a plurality of eccentrically mountedand driven gear-wheels rolling on the fulcrumgear wheels respectively,and having also a gear rolling on the secondary-gear wheel, a handle oroperator and operating connections between the severalfulcrum-gear-controlling means and the said handle or operator wherebythe said fulcrum-gears are all controlled by the said same handle oroperator.

4. The combination of instrumentalities herein described as a revolubleprimary shaft, an eccentric fixed thereon, a secondary-gear wheelconcentric with the primary shaft and revoluble independently thereof, aplurality of fulcrum-gear wheels concentric with the primary shaft andrevoluble independently thereof and of each other, a plurality ofeccentrically mounted and driven gear-wheels rolling on the respectivefulcrum-gear Wheels, and having also a gear rolling on thesecondary-gear wheel,said plural gears and hence the secondary gearrotating respectively forward and backward with respect to the primaryshaft when the respective fulcrum-gears are held, independent means forcontrolling the rotation of said advancing and backingful- Crum-gears,and also for controlling the rotation of the secondary gear, a handle oroperator, and operating connections between said handle or operator andthe said plural fulcrum-gear-controlling means andsecondarygear-controlling means, whereby the said same handle controlsthe fulcrum-gear-controlling means and the seconda1'y-gear-controllingmeans.

5. The combination of instrumcntalities herein described, namely arevoluble primary shaft, a plurality of eccentrics fixed thereon, aplurality of fulcrum-gear wheels concentric with said shaft andrevoluble independently thereof, and of each other, means forcontrolling the rotation of the fulcrum-gear wheels independently ofeach other, a plu- IOO IIO

rality of secondary gear Wheels concentric In testimony that I claim theforegoing as With the primary shaft and revoluble inde- 'my invention Ihave signed my name, in pres- Io pendently thereof, and a plurality ofrolling ence of two witnesses, this 23d day of April, Wheels mountedloosely on the respective ec- 1h97.

centrics, each rolling Wheel liatvingaJ plurality GEORGE B. BIRRELL. ofgears rolling on the respective fulcrum- Witnesses: gear Wheels and alsoa. gear rolling on the re- J OS. D. DONALD,

spective secondary-gear wheel. E. M. HUGENTOBLER.

